Acute Toxicity of Pesticides (Table 9)

Do not allow pesticides to contact your skin. Read
and follow all safety precautions on labels.
After handling pesticide, wash hands and face
before eating or smoking. Instruct your family, coworkers
and farm laborers on pesticide safety
procedures. Post safety rules and emergency
information where workers will see them.
Apple growers sometimes need to use pesticide
in areas where residences, cropland, pasture, or
bodies of water are nearby. Pesticide drift from
orchards to off-target areas presents a hazard. Avoid
application when conditions favor drift.
FIELD USE AND CARE OF RESPIRATORS
Wear the label-recommended respirator with a
filter for powders and an
activated charcoal filter for
organic vapors. Write the date
of first use on the cartridge.
Change the filters and
car-tridges after the number of
hours specified, or more often
if breathing becomes diffi-cult
or if pesticide odor is
detected. Respirators do not
provide adequate protec-tion from inhalation of
pesticide dust, mist or vapors when mixing pesticide
in closed or poorly ventilated areas.
The respirator should be fitted properly on the
face, not too high on the nose, with narrow portion
over the bridge of the nose, and chin cup contacting
under side of the chin. Headbands should be adjusted
just tight enough to insure a good seal. Refer to the
directions for respirator fit testing which should be
included with the respirator packaging.
Remove filters and cartridges and wash face
piece with soap and warm water after use. Dry face
piece with a clean cloth and/or place face piece in a
well-ventilat-ed area to dry. Store respirator, filters,
and cartridges in a clean, dry place — preferably in a
tightly closed plastic bag.
Other Safety Equipment
• Chemical resistant gloves.
• Personal protective clothing, such as rubber apron,
coveralls and cap.
• Chemical resistant work shoes or boots.
• Chemical resistant goggles.
ACUTE TOXICITY OF PESTICIDE
A pesticide’s hazard to warm-blooded animals,
including humans, is usually determined in relation to
the way it enters the body. Methods of entry include
the respiratory system, digestive system and skin. The
greatest hazard is from pesticide entry via the
respiratory system (inhalation).
Pesticide toxicity by this route is
not much different from that of
intravenous injection because
membranes of the lungs that
separate air from blood are
extremely thin, and absorption is
therefore very rapid (this is also
true for the eyes). Oral absorption (through the
digestive tract) is the next most hazardous avenue for
poisoning. Dermal (skin) absorption is less immediate
than respiratory or oral. However, there is
considerable variation in the rate of penetration
through the skin by different materials and
formulations.
When spraying, many airborne spray particles
are trapped in the secretions of the upper respiratory
tract and swallowed, thereby providing exposure by
inhalation and ingestion. Assuming that the person
applying the pesticide takes adequate precaution
(respirator, goggles, etc.) to prevent this type of
exposure, dermal toxicity is probably a more realistic
index of occupational hazard than oral toxicity.
DANGER — POISON, WARNING, CAUTION:
One of these “signal words” appears on the
label of every pesticide. Acute (or immediate, single
dose) toxicity is reported as an LD50 value (see Table
9). The LD50 for a chemical is the dose that has
been found in controlled experiments to kill 50% of a
large number of test animals. The LD50 dose is
usually expressed as the number of milligrams (mg) of
pure active ingredient per kilogram (kg) body weight
of the test animals. The lower the LD50, the more
toxic the chemical.
Because the LD50 is based on animal tests,
uses pure active ingredient rather than formulated
product, and does not account for individual
sensitivity, it does not necessarily represent the toxic
dose for an individual human. The LD50 of a
chemical gives no information on the possible longterm
health effects from repeated exposure at low
levels.
READ THE LABEL FOR PRESCRIBED SAFETY EQUIPMENT AND PRECAUTIONS!
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Table 9 – Acute Toxicity of Apple Pesticides.
LD50 for test animals
(mg technical chemical
per kg body weight)
Chemical
Oral (Rat) Dermal (Rabbit)
acetamiprid (Assail) 417 > 2,000
abamectin (Agri-Mek) 300 > 1,800
AVG (ReTain) > 1,840 > 2,000
azadirachtin (Neemix) > 5,000 > 2,000
azinphosmethyl (Guthion) 4 150-200
Bacillus thuringiensis toxin nontoxic
basic copper sulfate (Basicop, etc.) 472 ---
benomyl (Benlate) > 10,000 >10,000
benzyladenine (Accel) 1,300-2,125 ---
Bifenazate (Acaramite) > 5,000 > 2,000
captan 9,000 --- 1
carbaryl (Sevin) 246 ---
chlorophacinone (Rozol) 3 ---
chlorpyrifos (Lorsban) 96-270 2,000
cinnamaldehyde (Valero) --- ---
clofentezine (Apollo) > 3,200 ---
copper hydroxide (Kocide) 1,000 ---
copper oxychloride (COCS) 1,131 > 2,000
cyprodinil (Vangard) > 5,000 > 2,000
dazomet (Basamid) 519 > 2,000
diazinon 1,250 > 2,020
dichlobenil (Casoron) > 4,460 > 2,000
dicofol (Kelthane) 570 2,000-5,000
dimethoate (Digon) 235 400
diphacinone (Ramik) 7 ---
diuron (Direx, Karmex) > 5,000 > 5,000
dodine (Syllit) 1,000 1,500
endosulfan (Thiodan, Phaser) 160 359
esfenvalerate (Asana XL) 458 > 2,000
ethephon (Ethrel) 3,030 1,560
fenamiphos (Nemacur) 11 71
fenarimol (Rubigan) 2,500 ---
fenbutatin-oxide (Vendex) 2,631 > 2,000
fenpropathrin (Danitol) 71 > 2,000
ferbam (Ferbam Granuflo) > 5,000 > 4,000
fluazifop-butyl (Fusilade) 3,328 ---
formetanate HCl (Carzol) 15-26 >10,000
fosetyl-Al (Aliette) 5,000 > 2,000
glufosinate-ammonium (Rely) 2,000 > 4,000
glyphosate (Roundup) > 5,000 > 5,000
hexythiazox (Savey) > 5,000 > 5,000
imidacloprid (Provado) 450 > 5,000
indoxacarb (avaunt) 687 > 5,000
insecticidal soap (M-Pede) 16,900 > 5,000
kresoxim-methyl (Sovran) > 5,000 > 2,000
mancozeb (Dithane, etc.) 11,200 >15,000
LD50 for test animals
(mg technical chemical
per kg body weight)
Chemical Oral (Rat) Dermal (Rabbit)
maneb (Manex) 7,990 > 5,000
metalaxyl (Ridomil) 669 > 3,100
methidathion (Supracide) 44 200 1
methomyl (Lannate) 17-24 5,880
methoxyfenozide (Intrepid) > 5,000 > 5,000
metiram (Polyram) > 6,810 > 2,000
myclobutanil (Nova) 1,600 > 5,000
NAA (Fruitone-N, K-Salt Fruit Fix) 1,000 ---
NAD (Amid-thin) 1,690 > 2,000
napropamide (Devrinol) > 500 ---
norflurazon (Solicam) > 8,000 >20,000
oil (refined petroleum distillate) > 15,000 > 5,000
oryzalin (Surflan) > 10,000 ---
oxamyl (Vydate) 5 2,960
oxyfluorfen (Goal) > 5,000 >10,000
paraquat (Gramoxone Extra) 150 --- 1
pendimethalin (Prowl) 3,956 > 2,200
permethrin (Ambush, Pounce) 430-4,000 > 2,000
phosmet (Imidan) 147-316 > 4,640
promalin (Promalin) 5,050 5,050
pronamide (Kerb) 8,350 > 3,160
pyrethrum 1,500 > 1,800
pyrethrin & rotenone (Pyrellin EC) 1,500 ---
pyridaben (Pyramite) 820-1,930 > 2,000
pyriproxyfen (Esteem) > 5,000 > 2,000
rotenone 132–1,500 ---
sethoxydim (Poast) 3,200 > 5,000
simazine (Princep) >5,000 > 3,100
sodium methyldithiocarbamate 812 > 2000
(Vapam)
spinosad (SpinTor) >5,000 > 5,000
streptomycin (AgriMycin) 9,000 --- 2
sulfosate (Touchdown) 750 > 200 1
sulfur > 5,000 > 5,000 2
tebufenozide (Confirm) > 5,000 > 5,000
terbacil (Sinbar) 5,000 ---
thiabendazole (Mertect 340-F) 3,100 ---
thiophanate-methyl (Topsin M) 7,500 ---
thiram 1,000 > 5,000 1
triadimefon (Bayleton) 1,000 > 5,000
triflumizole (Procure) 1,057 > 5,000
trifloxystrobin (Flint) > 4,000 > 2,000
zinc phosphide 46 ---
ziram 1,400 > 6,000
2,4-D (Amine 4, Saber) 500-949 ---
--- = unknown; > = greater than; 1 - Irritating to skin, mucous membranes; 2 - May cause skin reaction.
Note: Chemicals for which at least one formulation carries the DANGER signal word because of acute toxicity or other
hazard are in bold letters. Different formulations of the same active ingredient can have different signal words.
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Toxicity Category LD50 Oral LD50 Dermal
& Signal Word (mg active ing. (mg active ing.
on Label per kg body weight) per kg body wt.)
I DANGER 0 to 50 0 to 200
POISON
II WARNING >50 to 500 >200 to 2,000
III CAUTION* >500 to 5,000 >2,000 to 20,000
IV none* >5,000 > 20,000
* Category IV material may have Caution signal
word due to skin irritation or other hazard.
In addition to oral or dermal acute toxicity, a
pesticide may also carry the DANGER — POISON,
DANGER, or WARNING signal words because of
other potential hazards, such as inhalation toxicity or the
ability to cause severe eye or skin damage
LABEL COMPLIANCE
Under the present EPA regulations, pesticides
may be applied:
• at a different rate per 100 gallons dilute than stated
on label as long as the application stays within the
dose per acre limit;
• at a lower rate per acre than on label; and
• less frequently than on label.
IMPORTANT — it is illegal to:
• increase amount applied per acre (overdosage);
• use shorter intervals between sprays than minimum
interval stated on label; and
• shorten intervals to harvest (illegal residues on
crop).
State regulations may be more restrictive than those of
the EPA.
PROTECTING WATER QUALITY
Apple growers have a responsibility to prevent
pesticide from contaminating surface bodies of water
and groundwater supplies. Over 90% of the rural
population in the U.S. depends on groundwater as
their supply of drinking water. Groundwater is very
difficult to clean if it does become polluted. Listed
below are a few practices that can help prevent water
contamination. Contact Extension for more
information.
• Consider the potential for rinse water, spills,
application or erosion to create pesticide laden runoff
which can reach a surface body of water. If
you do not have a self-contained mixing pad, use
an area where the run-off risk is low. If you are
working near a stream or pond, do not allow runoff
to occur.
• Use an anti-backflow device when filling the spray
tank.
• Periodically change the location of field mixing
areas. Be aware of the location and condition of
wells, stay at least 50 feet away from wells.
Special caution is needed around wells with
cracked casings.
• Be aware of the soil types, geology, and depth of
water table in your local area. The potential for
pesticide leaching into groundwater is generally
greater on ledge, sandy soils, or other soils low in
organic matter. The risk increases when the water
table is close to the surface. Try to choose
pesticides with a low leachability hazard if you are
working under these conditions.
• Keep spray equipment accurately calibrated.
• Use proper procedures for pesticide storage and
disposal. Keep pesticide storage and mixing areas
away from streams, ponds, and springs.
RESTRICTED ENTRY INTERVAL
The REI values listed in Table 10 are the best
information available as of November 2002.
Manufacturers may write the label with a longer REI
than required by the EPA, or the EPA may change
its minimum REI requirement. To know the use
restrictions for a pesticide you must READ THE
LABEL!
PESTICIDE RESIDUE TOLERANCES
Federal laws warn that food shipments bearing
residues of pesticide chemicals in excess of established
tolerances will be contraband and subject to seizures as
“adulterated.” This applies to both raw and processed
foods.
The amount of pesticide residue in or on a
food material at harvest must fall into established
tolerances, expressed in “parts per million” (ppm). The
actual amount of pesticide chemical found in a food at
harvest depends in part on the amount applied to the
crop and the length of time since the last application.
Therefore, growers are responsible for strictly
following label information as to:
• maximum spray dosage, and
• the preharvest interval: which is time between the
final pesticide application and harvest.
The FDA advises pesticide users to follow
directions on recently registered labels, so they do not
exceed the residue tolerance for any material. Use the
following table as a general guide, but verify the
preharvest interval by checking the label before using the
product. Table 10 refers to use on apples only.
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